Spray gun



I. S. PRESCOTT June 2, 1953 SPRAY GUN '2 Sheets-Sheet 1 Original Filed Jan. 5, 1948 w 9.. s m

INVENTOR.

Attorneys June 2, 1953 s. PRESCOTT SPRAY GUN 2 Sheets-Sheet 2 Original Filed Jan. 5, 1948 INVENTOR. [Sada *5: Prescoi'i' BY @flMflgMfiZfM At torneys R Q n n bm Q 2 no \Q 8 vw N6 8 0w Patented June 2, 1953 UNITED STATES PATENT OFFICE SPRAY GUN Isaac S. Prescott, Orlando, Fla.

Original application January 5, 1948, Serial No.

549. Divided and this application October 24, 1950, Serial No. 191,891

'3 Claims. 1

This invention relates to devices for sprayin liquids, and more particularly to devices of the character commonly known as spray guns and used for spraying fruit and vegetable trees and plants with insecticide, fungicide and other solutions.

The principal object of the invention is to provide a novel leak-proof structure for mounting a spray gun on a boom or other support and for readily adjusting and maintaining the position of the gun and the direction of its spray relative to the support.

Another object is to provide an improved mounting for a spray gun which will permit rapid adjustment of the gun to vary the direction of spray and maintenance thereof in adjusted position without the use of locking means.

A further object is 'to provide a spray gun mounting structure of the character described which is adaptable to any of the various types of supports or booms available on the market, and which will prevent the leakage of spray liquid even when the latter is supplied to the gun under relatively high pressure.

These and other objects, including that of facilitating and minimizing the expense of manufacture, assembly and repair of spray guns, will appear more fully upon consideration of the detailed description of the embodiment of the invention which follows. In this connection, although only one specific form of spra gun is described and illustrated in the accompanying drawing, it is to be expressly understood that this drawing is illustrative only and isnot to be construed as defining the limits of the invention, for which latter purpose reference should be ha to the appended claims.

Referring now to the drawing, wherein like reference characters indicate like parts throughout the several views:

Fig. l is a side elevation of a single nozzle spray gun embodying the present invention, including a showing of a fragment of a spray boom to illustrate the manner in which the gun is adapted to be mounted;

Fig. 2 is an axial cross section of the spray gun of Fig. l withcertain parts shown in full;

Figs. 3 and 4 are enlarged end and side elevations, respectively, of the nozzle whirl plate embodied in the gun of Figs. 1 and 2;

Fig. 5 is an enlarged axial cross sectionof the spray nozzle disc or tip of the spray gun of Figs. 1 and 2; and

Fig. 6 is a transverse section of the gun body taken on line 6-6 in Fig. 2.

The single nozzle spray gun shown in the drawing comprises as its principal elements a body member I l, a gun tube 1 2 fixed at one end to the body member H, a spray nozzle assembly indicated generally at It removably connected to the other end of the tube 2, a packing gland H and nut l5 forming a leak-proof closure for the end of body member H opposite that to which the tube 12 is connected, valve means for controlling the discharge of spray material from the nozzle assembly it including a valve operating rod I6 one end of which passes through the packing gland and nut assembly and projects outwardly from the body member H, a valve operating handle I! fixed to the outer end of the rod l6, and a structure for mounting the spray gun on a boom or other support comprising a body supporting tube i8 connected at one end to the body member H, a mounting nut 19 into which the other end of the supporting tube 18 is adjustably threaded, and a packing nut 20 for preventing leakage of liquid through the threaded connection between the supporting tube l8 and mounting nut l9. As indicated in Figs. 1 and 2, the mounting nut I9 is adapted to be threaded onto a suitable nipple 21 forming part of a boom or other support 22, such, for example, as that disclosed in my Patent No. 2,444,367, dated June 29, 1948.

The body member H consists of a substantially rectangular block of metal, such as brass, having a cylindrical bore or passageway 23 extending therethrough, the body member being internally threaded at both ends of passageway 23 to receive the similarly threaded ends of gun tube 12 and packing gland M, respectively. 'The tube I2 is coaxial with the passageway 23 in the body member and is externally threaded at its outer end to receive the spray nozzle assembly l3 consisting of a nozzle body 24, nozzle cap 25, whirl plate 26, gasket 2'! and nozzle disc 28, the last three elements being interposed between, and held in properly assembled relationship by, the outer end of nozzle body 24 and nozzle cap 25.

The inner end, of nozzle body 24 is internally threaded for engagement with the outer end of tube I2, and is provided with a transverse partition 29 having a central opening 3|] of reduced diameter, said partition abutting the end of tube it. when the gun is assembled. The outer end of nozzle body 2i beyond the partition 29 is cylindrically recessed to provide a chamber 3| of slightly larger diameter than the passageway 23 in body member H, the inner end of the chamber 3| formed by the partition 29 having a beveled and countersunk configuration as indicated at 32 in Fig. 2.

The valve operating rod [6 extends axially through the passageway 23 and the bore of tube l2, and is provided with a main valve 33 adapted to control the flow of spray material through the central opening 36 in partition 29, the inner edge of the plane wall of said partition which abuts the end of tube l2 forming the seat for valve 33. The valve rod I6 is also provided with an extension 34 of reduced diameter which passes outwardly through the opening 33 and carries at its outer end another or secondary valve 35 adapted to control the flow of spray liquid through the central opening 36 in the whirl plate 23. The

maximum diameter of the secondary valve 35,

which is that of its substantially cylindrical seat engaging portion 31, is slightly smaller than the diameter of opening 39 in partition 29 so as to facilitate assembly and disassembly of the spray gun. The valve operating rod is also carries a centering guide member 38 fixed thereto adja cent the main valve 33, which member is generally triangular in shape as indicated in Fig. 6, the apices of said member being rounded and having sliding engagement with the bore of tube l2 so as to center the valve rod I6 in said bore, while the open spaces between said apices enable the spraying solution to flow freely past said member.

The whirl plate 26, the details of which are shown in Figs. 2, 3 and 4, consists of a relatively thin annular rim 39 of sheet metal lying in a plane perpendicular to the axis of the central opening 36, and a hollow cylindrical boss 46 which is fixed to the inner periphery of the rim 39, as by the clinched connection indicated at 4|, and projects axially inwardly from the rim into the chamber 3| of nozzle body 24. The axial length of the boss 40 and its inside diameter are such that the cylindrical portion 31 of secondary valve 35 slidably engages the bore of boss 40 so as to close the central opening 36 in the whirl plate both when the main valve 33 is closed and when it is within a predetermined distance of its seat in partition 29, at which times the spray material is discharged from the gun in the form of a relatively wide angle, fog-like spray of relatively short carrying distance, created by passage of the spray material through only the tangential openings 42 of the whirl plate (next to be described). The boss 46 is short enough, however, to permit withdrawal of the secondary valve 35 when the main valve 33 is withdrawn further from its seat than the position indicated in Fig. 2, at which time the secondary valve 35 will occupy a position such as that indicated in broken lines in Fig. 2, and the spray liquid will pass through both the central opening 36 and the tangential openings 42 of the whirl plate and will be discharged as a more concentrated conical spray capable of carrying to a greater distance.

In the form of whirl plate shown in Figs. 2, 3 and 4, the tangential openings 42 which impart the whirling movement to the spray material as it passes from the chamber 3| to the nozzle disc 28 are formed by cutting the rim 39 along radial lines, as at 43 in Fig. 3, and then pressing arcuate sections of said rim outwardly (to the right as viewed in Figs. 2 and 4) to form trough-likecom duits 44 of varying depth with respect to the plane of rim 39, said conduits terminating in the substantially semicircular openings 42 which lie in planes perpendicular to the rim 39 passing through the radial lines 43. Any suitable number of tangential openings may be formed in the whirl plate, although the preferred arrangement comprises four such openings as illustrated in Fig. 3.

Cooperating with the whirl plate to form the spray discharge from the gun is the nozzle disc 28 consisting of an annular rim portion 45 lying parallel to the rim 39 of the Whirl plate and spaced therefrom by the gasket 21, an elongated nose portion 46 which projects outwardly from the rim portion 45 through a central opening in the nozzle cap 25, and a bushing 41 seated in the nose portion 46, the bore of which bushing forms the spray discharge orifice 48 of the nozzle as sembly. The nose portion 46 is formed integrally with the rim portion'45 and is frusto-conical in shape both outside and inside, the orifice-forming bushing 41 having a similar shape externally and being pressed into the nose portion with a r diameter.

friction fit so as to be readily replaceable. The bushing 41 is preferablymade of hardened stainless steel in order to prolong its usefullife, 'although the rim and nose portions 45 and 46 are usually made of a softer metal, such as brass.

In order to increase the effective distance of spray discharge from the gun, the bore of bushing 41 tapers or converges toward the discharge end throughout the major portion of its length, as indicated at 49, and terminates in a relatively short section 58' of uniform diameter. The straight section 50 may vary in diameter from to and since the bushing 41 is replaceable, the desired size of spray discharge orifice may be readily obtained by simply selecting a bushing wherein the section 59 is of the proper It has been found that excellent results are obtained by limiting the length of the straight section 56 to approximately A in a disc wherein the nose portion 46 projects approximately .6 from the rear face of the rim portion 45, and by tapering the bore section 49 at an angle of approximately 10.

The whirl plate 26, gasket 21 and nozzle disc 28 are held in properly assembled relation with respect to one another and to the nozzle body 24 by the nozzle cap 25 which has an internally threaded rim 5| adapted to thread onto the externally threaded outer end of nozzle body 24. and an annular wall 52 adapted to engage the rim portion 45 of the nozzle disc and having a central opening through which the nose portion 46 of said disc projects. When the elements of the nozzle are assembled, the annular space 53 between the whirl plate and nozzle disc constitutes a whirl chamber into which the spray material issuing from the tangential openings 42 discharges and in which it sets up the whirling motion that produces the fog-like characteristic of the spray.

Movement of the main and secondary valves 33 and 35 from and to their respective seats is controlled by rotation of the handle 1'! which is fixed to the end of the valve operating rod I6 opposite that carrying the valves, rotation of the handle l1 being converted into longitudinal movement of the rod l6 and valves 33 and 35 by means of a threaded connection between the handle and an extension 54 of the packing nut I5.

As shown in Fig. 2, the valve rod l6 extends outwardly of the gun body member through the packing gland l4 and packing nut 15, including the latters extension 54. and terminates in a threaded portion 55 to which the handle I1 is fixed. A suitable packing 56 is provided around the rod l6 between the gland l4 and nut l5 so as to prevent leakage of the spray material from the :body member outwardly along the rod,

comma and the packing gland i4 is provided with a looking screw 51 for preventing rotation of packing nut 1-5 relatively to "the gland once the packin 56 has been properly compressed. The outer portion of the handle i! is provided with a smooth bore 58 of a diameter such as to meceive the threaded portion '55 of the rod H6, whilejthe inner portion of the handle is recessed to receive an intern-ally threaded ferrule 5!! which surrounds and has threaded engagement with the extension 51; of the packing nut 15. Although the ferrule so may be fixed to the handle I! in any suitable "manner, the embodiment disclosed comprises a handle of hard rubber or other plastic materinil molded around the shank of the fer-rule '59 which :isprefera bly poov-ided with circumferential ridges to prevent axial displacement. of the two .ele-- ments. It will he understood that the pitch of the cooperating threads of ferrule '59 and packing nut extension 54 "is great enough to enable relatively rapid opening and closing 02f the valves, hut also small enough to permit the proper degree of adjustment thereof for the spraying con ditions desired and to maintain the valves in any adjusted position notwithstanding the ax'iafl pressure exerted by the spray material. I

The handle 11 "is lined to the valve operatinu rod [6 "by a pair of mute :61 and 352, the 56;! being threaded all the way on the portion 55 of the rod and, with a isuitahle washer 53, serum as a stop for the base of ferrule 55 when the and of the mod is :passed thuougih the bone 58 of the handle, while the 52 and its washer M awe housed in a necess 65 the outer end of the loandle and are screwed up tight against the Mass of said recess so as to clamp the portion of the handle sumoundingthe hone 58 between two nuts. With this construction, rotation of the handle 1. 5 and its resulting axial movement due to the threaded engagement between the ferrule :59 and packing not extension 54 produoes axial mowc- .ment of the valve openatin g "rod b5 and the mhles $3 and .35 carnedthereby. In order to positively limit movement .Olf valve and 26 :in value 9mm direction to :a desired maximum, the portion of the rod located in body member :14 may he provided with a tnanswerse pin 55 which is adapted to come into enga ement with the inner tace of packing gland :14 when the fame fully opened.

Referring now to the improved construction hi1 the spray gun is adapted to he summon mounted on a spray boom or support, the supporting tube 18 is threaded into the mods member 411 intenmediate its ends with the axis of the tube :at right to that of the lsaody passageway .23, the hereof the tube being in free communication with said nassageway ifior supplynine! spray liquid to thelatter underpressure. 33km :other end of tube I B (is also externally threaded over a substantial distance for engagement cooperating threads toizmed internally or the portion 6] (the upper portion as viewed in'Figs 1 and 2) of mounting nut J9, being evident from -Fig. 2 that the threaded portion of the tube is of considera ly reater axial extent than the 00!- operating internally thizeaided portion of the not. The exterior of portion 63! of the mounting nut is likewise threaded to receive the {internally threaded end of the hollow cylindrical ibodygotf the packing :nut '28, while the closed end 70 '68 of the packing nut ifrictionally engages the smooth cylindrical portion of supporting tube i8 intermediate its threaded ends. A suitable loakproof packing "69 filis the space between the closed end portion '68 of the packing nut and the adiacont end of the portion 1 or the moumz'ingnut; and is tightly compressed in said space mound the 18 so as to prevent leakage of sprat'll'iqlfid through the gun adjusting thueaded connection between the tube 18 and mounting nut 439. frictional engagement with the tube :18 resulting {2mm compressional the packing 59 in manner also serves to the sun in any posh :tion to which it may be adjusted "by rotation of tube 1 8 melativvejly to mounting not 49,

As shown fhest Fig. 2, the body of mounting out it is provided with a :frusto-oomcai access 10, having a diameter greater than that of the threaded portion 61, into which the end of tube L8 projects as the latter is threaded downwaodly as viewed in Fig. 2, The outer portion of rece s 10 is threaded to receive the similamy tapered and threaded end of a nipple :21 or other suitable element coming part of the spray 22 or other support on which the :gun adapted to he mounted, and conical taper of the cooperat lin threaded elements facilitating a liquid-tight connect-ion therebetwoon.

when the spray gun is assembled and mounted in the manner indicated Figs. 1 and 2, the spray'ifls solution is supplied under pressure to the interior of the {boom or support .272 any suitable manna-1;, as, .for example, in my meuionsly mentioned Patent No. 2,444,363, 'it'he solution upwardly, as viewed in thengures. through the nipple 24,, mounting not I 9 and l8 into the passageway 23 of the body member M and thence through the ,gun tube .422 to the nozzle assembly, If the handle I] is so rotated with respect to the threaded extension 54 of the packing nut t5 that the valves occupy the positions illustnatod in Elie. 2, wherein the main valve 33 is partially open but the secondary valve 35 is still closed, the spray liquid will flow through the opening A0 in the partition '29 into the chamber 3;], then through the tangential openings 4120f the whirl plate 26 into the mom chamber 53, and finally thmu gh the room/eyeing and straight portions :49 and 5.0 of the princetorming bushing 41'! of the nozzle disc 28,, issuing tron: the mince 48 in the term of a wide angle, ifogelike spray of relatively short carryin distunes. I: the handle (I; is further adjusted so as to withdraw the secondary valve 35 the position indicated in broken lines in .Fig. the spray solution then pass through the central opening Q16 in the whirl plate as well as through the tangential openings 42,, the mesult that th army issuing from the omifioe A8 is more concentrated and carries to a smaller distance than when only the [main waive 33 is open The characteristics of the spray may, of atom-so, he varied over a relatively wide nange by suitable adjustment of the positions of the valycsibetween the limits permitted by zt'hfi wfiioions of (the transverse and the waive seats zfiormed by the namtition 2.8 and hose on.

.Dueto the rimprowed @oonstnuction of lihe means by which the sun :is mounted on the hoom or support, the :sun can :be adjusted instantly by hand to wary the direction of thespmy in two planes at angles to 9108 another, a, longitudinally and cironunxfemerrtialily melamine to the axis of nut '18, my simply -,gm'sping handle .43 and zrotatiug rthe .gun assembly about the axis of cube H8: and once the gun has been moved to any vdesired position, it will maintain that position without manual retention or mechanical Flocking. En addition to this feature of ready anti-notability the novel cooperation of the: parts of the mounting also effectively prevent leakage of the spray liquid, even when pressures as high as 1000 pounds per square inch are used.

There is thus provided by the present invention a new form of spray gun which embodies a number of improvements over similar devices heretofore available. For example, by providing the packing nut of the body member with a threaded extension cooperating with a similarly threaded portion of the handle, the valve adjusting mechanism is located entirely outside of the body member and out of contact with the spraying solution, thereby preventing corrosion and freezing of the threaded members by which the valve operating rod is moved. -The combination of the body supporting tube, mount ing nutand associated packing nut is also an improvement over prior devices of the same general type in thatit provides a leak-proof means for so mounting a spray gun on a support that the direction of the spray can be readily adjusted, and once the adjustment has been made, the gun will remain in the desired position without the necessity for manual support or the use oflocking means which have to be unlocked in order to make the adjustment. Another feature of the present invention is that the various elements of the gun are easily assembled and disassembled, so as to facilitate manufacture and repair, and the majority of the parts are individually replaceable. Further improvements reside in the novel form of nozzle disc which increases the effective distance of spray coverage with the same pressure on the spray material;- and in the inclusion of the removable orifice-forming bushing which both prolongs the life of the nozzle'assembly and also makes it possible to change the size of the orifice by simply replacing the bushing. The nozzle "assembly also includes an improved form of whirl plate of simple, inexpensive construction which is so designed as to also form the valve seat for the secondary valve.

While only one specific form of spray gun embodying the invention has been described and illustrated in the accompanying drawing, it will be obvious that the invention is not limited to the exact structure shown, and is equally adaptable to multiple nozzle spray guns as it is to the single nozzle gun illustrated. Various changes which will now suggest themselves to those skilled in the art may be made in the form, details of construction and arrangement of the parts without departing from the inventive concept. Reference is' therefore to be had to the appended claims for a definition of the limits of the invention.

This application is a division of Serial No. 549, filed January 5, 1948, now abandoned.

What is claimed is:

i. In a spray gun having a body member adjustably mounted on a support with a passageway in said body member adapted to receive the liquid to be sprayed from the interior of said support, means for adjustably mounting said body member on said support comprising a supporting tube connected at one end to said body member with its interior communicating with said passageway, a mounting nut into which the other end of said tube is threaded, said tube serving to conduct the liquid to be sprayed to the passageway within said body member and having an externally threaded portion of greater axial extent than the cooperating internally threaded portion of said mounting nut and being at all times unrestrlctedly rotatable with respect to said nut so as to permit adjustment of the position of said body member both longitudinally and circumferentially relative to the axis of said nut, said mounting nut having an internally threaded portion coaxial with and of greater internal diameter than the exterior of said tube by which said nut is adapted to be secured to said support, and means for preventing leakage of liquid from the interior of said mounting nut and tube through-the threaded connection therebetween.

2. In a spray gun having a body member adjustably mounted on a support with a passageway in said body member adapted to receive'the liquid to be sprayed from the interior of said support, means for adjustably mounting said body member on said support comprising a hollow supporting member connected at one end to said body member and externally threaded at the other end, a mounting nut having a first internally threaded portion cooperating with the externally threaded end of said supporting member and a second internally threaded portion coaxial with and spaced from said first portion by which said nut is adapted to be secured to said support, the portion of said mounting nut intermediate said first and second threaded portions forming a recess of greater internal diameter than the external diameter of the threaded end of said supporting member, the portion of said supporting member intermediate its ends having a smooth cylindrical exterior surface, a packing nut frictionally engaging the smooth exterior portion of said supporting member and threaded to the outside of said first internally threaded portion of said mounting nut, and a leak-preventing packing compressed between said packing nut, mounting nut and supporting member, said supporting member serving both to conduct the liquid to be sprayed to the passageway within said body member and, through its threaded engagement with said mounting nut, to adjust the position of said body member both longitudinally and circumferentially relative to theaxis of said nut.

3. In a spray gun having a body member ad- 'ustably mounted on a support with a passageway'in said body member adapted to receive the liquid to be sprayed from the interior of said support, means for adjustably mounting said body member on said support comprising a supporting tube connected at one end to said body 'memberwith its interior communicating with "saidpassageway, a mounting nut having a first internally threaded portion into which the other end of said tube is threaded and a frusto-conical- 1y recessed portion coaxial with and of greater internal diameter than that of said first internally threaded portion into which the end of said tube may project when the latter is threaded into said mounting nut, said recessed portion also being internally threaded for securing said nut to said support, said tube serving to conduct the liquid to be sprayed to the passageway with in said body member and being at all times unrestrictedly rotatable with respect to said mounting nut so as to permit adjustment of the position of said body member both longitudinally and circumferentially relative to the axis of said nut, the portion of said tube intermediate its ends having a smooth cylindrical exterior surface, a packing nut frictionally engaging the smooth exterior portionof said tube and threaded to the outside of said first internally threaded portion 9 of said mounting nut, and a leak-preventing packing compressed between said packing nut, mounting nut and tube.

ISAAC S. PRESCOTT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 365,068 Hendrick June 21, 1887 10 1,100,165 Waller June 16, 1914 Number 10 Name Date Steinmetz Mar. 23, 1920 Smith Dec. 7, 1926 Nash Dec. 1, 1931 Jenkins Nov. 15, 1932 Shields Nov. 20, 1934 Roselund Aug. 25, 1936 Griflith Dec. 26, 1944 Chapin June 20, 1950 

